Mobile IP has been widely accepted as a standard to support IP mobility in a wireless Internet environment to keep a session connected when a mobile host roams from subnet to subnet. Another emerging wireless network architecture that is gaining more and more popularity is the mobile ad hoc network (MANET), which can be flexibly deployed in almost any environment without the need of infrastructure base stations. In order to move to an all-IP environment, there seems to be a growing demand to integrate these two architectures together. Typically, mobile hosts are served by access points that can connect to them directly (in one hop). In this paper, we propose to extend access points to multiple MANETs, each as a subnet of the Internet, and discuss how to support Mobile IP in such environment. Such integration is beneficial to both societies. FromMobile IP’s prospective, Foreign Agents’ service areas are not limited to hosts within a single (wireless) hop any more. From MANET’s prospective, mobile hosts can immediately enjoy tremendous services already existing on the Internet through Mobile IP. This article reports our integration and implementation experience based on IEEE 802.11b wireless LANs. Issues such as overlapping ofMANETs, dynamic adjustment of mobile agents’ service coverages, support of local broadcast and various communication scenarios are addressed. Discussion also covers required adjustments of Mobile IP to support such architecture.